GCN Circular 15053
Subject
GRB 130727A: Fermi GBM detection
Date
2013-07-28T01:49:33Z (11 years ago)
From
Adam Goldstein at Fermi-GBM/UAH <adam.m.goldstein@msfc.nasa.gov>
A. Goldstein (ORAU/NASA MSFC) reports on behalf of the Fermi GBM Team:
At 16:45:20.91 UT on 27 July 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130727A (trigger 396636323 /130727698)
which was also detected by the Swift BAT (Stroh et al. 2013, GCN 15046).
The GBM on-ground location is consistent with the Swift position;
the angle from the Fermi LAT boresight is 134 degrees.
The GBM light curve consists of one main pulse with substructure
with a duration (T90) of about 13.0 s (50-300 keV). The
time-averaged spectrum from T0=-1.0 s to T0+12.0 s is adequately fit
by a Band function with Epeak = 118 +/- 17 keV, alpha = -1.1 +/- 0.1,
and beta = -2.2 +/- 0.1.
The event fluence (10-1000 keV) in this time interval is
(8.9 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured starting
from T0+6.1 s in the 8-1000 keV band is 11.1 +/- 0.6 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog.